Sterile Filtration and Bioburden Control for the Processing of Biologics

Proven filters from media development to final fill

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Protecting the bioreactor from unwanted organisms and contaminants

Sterile filtration ensures that everything entering the bioreactor meets requirements to optimize cell culture or fermentation growth. Incorporating prefiltration into this process will protect the life of the sterilizing filters and lower your overall filtration costs. Product solutions are discussed below.

Sterilizing and Bioburden Reduction Filtration in Biopharmaceutical Processes (1)


Downstream Sterilizing and Bioburden Reduction Filtration



Remove impurities before chromatography and assure sterility during final fill

Filtration is a vital component in assuring efficient operation and maximum output of chromatography systems in purification processes. Contaminants to be removed can include endotoxins - charged particles that can prematurely consume resin capacity - and organic or inorganic particles in base solutions, buffer solutions and cleaning solutions used to regenerate the columns between batches. Removing these contaminants optimizes column performance and keeps them operating at the highest level.

Sterile filtration of biologic drugs is a preferred method due to the product's heat sensitivity. Designing this process needs to be carefully done to avoid degradation and loss of product during final fill. Critical Process Filtration's application engineers work with you to assure proper testing and the right combination of filters.



Prefiltration of particle and microbial contaminants is accomplished with Critical Process Filtration's economical membrane and pleated depth media filters. 

Made from CPF's proprietary high capacity PES membrane, BCWPS Filters excel in protecting downstream filters. With its low binding characteristics, BCWPS filters are used for the clarification and prefiltration of products with high proteins and preservatives. Membrane based prefilters, such as the BCWPS offer greater retention than a depth filter.

With its high flow rates and particle removal capability, our PGD Prefilters are made with pleated fiberglass depth media and have a high contaminant holding capacity. PPD Prefilters, constructed with pleated polypropylene depth media, are a great choice for retention of fine particles and have broad chemical compatibility for use in a variety of applications. 

CPF's HLP Prefilters, constructed with high-loft pleated polypropylene depth media, are designed to work with fluids that have high solids content or contamination. HLP filters combine superior filtration capacity with exacting retention of fine particles.

When a pre-column endotoxin prefilter is needed, the GPC Prefilter is a positively charged PES membrane that will remove cell debris.


  • Biologics
  • Media & Buffers
  • Raw ingredients
  • Plasma/Serum
  • Process Water
  • Fill & Finish

Sterilizing & Bioburden Reduction Filters

With bioburden management beginning before the bioreactor and continuing downstream to final fill, Critical Process Filtration delivers high quality bioburden control and sterilizing filters made with PES membrane to assure a sterile product.

BPS Filters are made with PES membrane, available in single and dual layer configurations. They are designed to reduce bioburden contamination and are utilized in products with high proteins and preservatives that can adsorb to media. 

Our PPS Filters consist of a double layer of PES for the most critical applications and have low binding characteristics for filtering ingredients with preservatives and protein solutions that can adsorb to media. For increased capacity when filtering liquids with high particle loads, HPPS Filters provide a dual layer PES membrane configuration - an integrated prefilter layer with an asymmetric PES final filter. This 2-in-1, prefilter and sterilizing model is a good solution when space is limited to one housing.

Where mycoplasma is an issue, CPF recommends 0.03 micron filters for capturing small deformable particles that might penetrate through a traditional 0.2 micron filter. Use of 0.03 micron filters in a validated process ensures sterile, mycoplasma-free serum and plasma.  

If endotoxin removal is necessary, the PPC Filter sterilizes and is positively charged to remove gram-negative bacteria debris. 

Protecting tank contents and the process environment

CPF's PTR Filters can prevent environmental and process gas sources of bacteria and contaminants. These hydrophobic sterilizing filters are made with Polytetrafluoroethylene (PTFE) membrane to capture microbials as air/gas enters a tank. Likewise, as air/gas is released from the tank, the PTR filter protects operators in the surrounding work space.

Product sizes scale for lab use, process development and production arena and are available in cartridges and single-use capsules.


Filtration solutions for producing point-of-use, WFI and bulk water.


Bio/pharmaceutical Water Filtration

Verification/Validation Services

Critical Process Filtration will test your process stream on our product to ensure filter performance.

  • Verifying that our filters will meet your performance goals
  • Validating performance set forth by regulatory bodies
  • Assisting with protocol development and execution
Connect with an Applications Engineer about verifying/validating your filters.


Quality Assurance and Standards

Critical Process Filtration filters are designed for use in cGMP compliant processes. Our state-of-the-art manufacturing facility and quality-management system both meet ISO 9001:2015 standards. Each operation from assembly and test to cleaning, drying, and packaging is done in appropriately rated clean rooms, and each filter is assigned a lot code to ensure the traceability of manufacturing data and materials. A sophisticated MRP system collects and processes real-time data from manufacturing centers and inspection points. 

USP Biosafety and FDA Compliance

The materials used to construct pharmaceutical-grade filters are non-toxic and meet the requirements for the MEM Elution Cytotoxicity Test and the requirements for Biological Reactivity Tests in the current version of the United States Pharmacopeia (USP) for Class VI - 121 °C Plastics. Critical Process Filtration filters comply with Title 21 CFR sections 210.3 (b)(6) and 211.72, for non-fiber-releasing filters. The levels of bacterial endotoxins in aqueous extracts from pharmaceutical-grade filters are below current USP limits as specified for water for injection.